[llvm] X86: Fix asserting on bfloat argument/return without sse2 (PR #93146)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,1441 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=i386-linux-gnu < %s | FileCheck -check-prefixes=CHECK,NOSSE %s
+; RUN: llc -mtriple=i386-linux-gnu -mattr=+sse < %s | FileCheck -check-prefixes=CHECK,SSE %s
+
+; Make sure no assert without SSE2 and bfloat. Issue 92899
+
+define bfloat @return_arg_bf16(bfloat %x) {
+; CHECK-LABEL: return_arg_bf16:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    flds {{[0-9]+}}(%esp)
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arsenm wrote:

But you could just as well replace half in ABI contexts with float, as is done for bfloat. You can make either decision, the instruction support doesn't really change this 

https://github.com/llvm/llvm-project/pull/93146